A filtering apparatus of prior art usually includes an box-shaped equipment housing and several filter nets disposed in the equipment housing, allowing a fluid to flow through the filter nets along a filtering direction to achieve filtration.
However, such filtering apparatus is hard to be flexibly adapted to suit various requirements of filtration. For example, a box-shaped equipment housing appears to be bulky and inconvenient when less filter nets are required. On the contrary, if more filter nets are required, such filtering apparatus does not allow extra filter nets to be disposed in the equipment housing, which requires the purchase of another suitable filtering apparatus. In addition, a filtering apparatus with smaller filter area is hard to used in a situation where larger filter area is needed. However, a filtering apparatus with larger filter area is bulky and inconvenient to use. On the other hand, it is costly to have a filtering apparatus made-to-order with required size or shape according to the requirement.